Induction-wattmeter.



I G. A. SGHEEFFER.

INDUCTION WATTMETER.

APPLIOATION FILED AUG. 31, 1910.

1,082,658. Patented Dec. 30, 1913.

4 EHEBTS-SHBET 1.

Witnesses:

G. A. SOHEEFPER.

INDUCTION WATTMETER.

APPLICATION FILED AUG. 31, 1910.

1,082,653. Patented Dec. 30, 1913.

4 SHEBTSSHEET 2.

G. A. SGHEEFPER.

INDUCTION WATTMETER.

APPLICATION FILED AUG. 31, 1910.

1,082,653, Patented Dec. 30, 1913.

4 sums-SHEET s.

WzLnassesx [2222672 607 W 1/0. M 6m fave Abafzeej @p G. A. SGHEEPFER.

INDUCTION WATTMETER.

APPLICATION FILED AUG. 31, 1910.

1,082,653. Patented Dec. 30, 1913.

4 SHEETSSHEET 4.

MAG/V5776 m 5 U6 0 e e w (v A ttarney UNITED STATES PATENT OFFICE.

GUSTAV-E A. SCHEEFFER, INDIANAPOLIS, INDIANA, ASSIGNOF, BY MESNE ASSIGN-MENTS, TO ROLLER SMITH 00., OF NEW YORK, N. Y., A CORPORATION OF NEWYORK.

To all whom it may concern:

Be it known that I, Gus'mvn A. SOHEEF- rnn, a citizen of the UnitedStates, residing at Indiana olis,.in the county of Marion and State ofndiana, have invented a certain new and useful Improvement in Induction-Wattmeters, of which the following-is a full, clear, concise, and exactdescription, reference being had to the accompanyingdrawings, forming a'part of this specification.

My invention relates to instruments for measuring alternating currentsof electricity, and is particularly directed to an integrating wattmeterof the induction type.

-It is the object of my invention to provide such a device, improved inoperation and construction, the latter features being particularly amatter of providing for convenient access to the various partstofacilitate inspection, adjustment and repair.

It is one of the important objects of my invention to overcome theundesirable vibrating or singing of the armature, a difliculty soprevalent in alternating current meters of the prior art. I eliminatethis difliculty by providing what may well be termed a magnetic cushionfor one bearing, the upper'bearing, of the armature shaft, the otherbearing being jeweled.

A further important feature of my invention lies in the provision of ageneral supporting unit in the way of a cradle upon which the coils, thearmature, the integrating mechanism, and the brake magnet, those partsusually requiring the 'most attention, are mounted. It is a feature thatthis cradle and the parts carried thereby can be removed bodily from themeter casing and that the cradle itself is so formed that easy accessmay be had to all the'parts carried it. A further feature of myinvention lies in the protective arrangement for the terminals, thisconstruction providing for complete insulation and protection againsttampering and unwarranted manipulation.

My invention is illustrated in the accompanying drawings in which-Figure 1 is a front elevational view of the device, the cover beingremoved and the parts being broken away' to reveal the interiorconstruction; Fig. 2 is a side eleva tional view of the device, partsbeing shown Specification of Letters Patent.

. Application filed August 31, 1910. Serial No. 579,942.

Patented Dec. 30, 1913.

in section on the plane of the broken line 22 of Fi 1, looking in thedirection indicated by t e arrows; Fig. 3 is a plan view of theoperating mechanism, the casing being shown in section taken on theplane of the line 3-3 of Fig. 1; Fig. 4 is an isolated front elevationalvlew of the disk armature, the means for supporting it, and two of theassociated coils; Fig. 5 is an isolated elevational view of one set ofcoils, showing the armature in section therebetween; and 'Fig. 6 is anenlarged isolated detailed view of the bearing which provides themagnetic cushion for the armature shaft.

The meter casing comprises two parts, a base part 7 and a cover part 8,these two parts being held together by means of thumb nuts 9, 9 havingthreaded engagement with the ends of the rods 10, 10 extending from theposts 11, 11, secured to the base part, and passing through registeringopenings in the cover part.' If desired each thumb nut is register wit-han-aperture 13 in the associated rod 10, through which apertures a wire14 may be passed, as shown in Fig. 3, the free ends of the wire beingconnected together by the seal 15, all to prevent un authorized accessto the interior of the case.

by means of a screw 18 and screws 19, 19

passing through the lugs 20, 20 and into the posts 21, 21, secured tothe part 7 by means of screws 22, 22. It is to be noted that the cradle17, in plan, is half octagonal in form, presenting an open front andthat the top of the cradle is spanned by the cross bar 23, while thebottom thereof is spanned by the cross bar 24. To the oblique sides 25,25, near the tops thereof, the laminated iron cores 26, 26 are securedby means of screws 27, 27. The cores 26 are each of complete rectangularshape, except for the gap 28, and upon one of the vertical legs of eachof these cores, a pressure coil 29 is mounted. The walls 25, 25 of thecradle 17 are, of course, cut out to accommodate these coils, as clearlyshown in Fig. 5.

ro-vided with a transverse aperture 12, which is adapted to Below eachof the cores 26 an iron core 30 is secured to the wall. 25 by means ofscrews 31, 31, this core being L-shaped and carrying the current coil 32on the vertical leg thereof. The vertical leg of the core 30 is disposedbelow the gap 28 in the core 26, and the upper end of the core 30 issufficiently spaced from the bottom of the core 26 to permit themovement of the armature disk therebetween, as will be described later.Here, again, the wall 25 is cut out to accommodate the coil. The ,core26 is formed as it is and is more or less definitely related to theresistance of the pressure coil so that the proper lag of the current inthat coil behind the current in the series coil may be obtained. Inorder to determine and maintain this lag to a nicety, a nonmagneticshading coil 33 is carried by the supporting member 34 in. closeproximity to the pole ends of the core 26, the supporting member 34;being secured to the cradle 17 by means of screws 35, 35 passing througha slot 36 in the former and having threaded engagement in the latter. Itis clear that this arrangement provides for the vertical adjustment ofthe shading coil so that the inductive effect may be properly regulated.

The lower bearing for the armature shaft is in the form of a jewel 37set in a pin 38 which is held in the sleeve 39, threaded and locked inthe aperture in the center of the cross piece 24, by means of the leafspring member tO extending from a post -11 secured to the cross piece 24by means of the screw 42, the leaf spring being clamped.

between the head of the screw and the post. The upper cross piece 23 isprovided with an opening registering with the central opening in thelower cross piece and in this opening the sleeve 43 is riveted, asclearly indicated in Fig. 6, the axis of this sleeve being, therefore,co-incident with the axis of the jewel bearing. In the sleeve 43 a pin44 of magnetic material is disposed, this pin being verticallyadjustable and being locked in any desired position by means of the setscrew 45 passing through the sleeve and engaging the pin. Between thebearings 37 and 14, the armature shaft 16 is disposed, this shaft beingprovided at its lower end with the steel pin 47 for cotiperation withthe jewel. The armature shaft proper is constructed of non-magneticmaterial, but the steel pin 48 secured in the upper end of the armatureshaft is the magnetic element which, extending into a bore in the par44, cooperates with that part magnetically as will be described later.The pin 44:, of course, is adjusted so that there will be just enoughplay for the proper rotation of the armature shaft. Secured upon thearmature shaft 46 by means of set screw 49 is a sleeve 50 ofnon-magnetic material which carries the aluminum disk armature 51, thisarmature being so disposed upon the shaft that it may between the polesof the iron cores, as clearly shown in the drawings. The disk 51 may belifted from its lower hearing by n'ianipulation of a screw 51cooperating with a leaf spring 51 having bifurcated end under the middleof the disk. The diameter of the armature is such that it may fit in thesupporting cradle 17 and is such that the pole ends of the magnetsupported on the oblique walls of the cradle will be near the peripherythereof. Secured upon the top of the cross piece 23, and under.thenon-magnetic retaining plate 52, by means of the screw 53 is thehorse-shoe magnet 54, one pole of which is disposed in close proximityto that part of the pin 41- extending above the cross bar 23. It isevident that thisstructure pro-ides for the ready adjustment of themagnet so that one of the poles thereof may be disposed more or lessclosely to the magnet pin 44, as desired. It is evident that if there isno play between the armature shaft and its bearings, it will beimpossible for the armature to rotate, and it is further clear that ifthe armature is to rotate under the inductive influence of the coils,there must be a considerable play between these parts, and it has beenfound in meters of the prior art that the alternating fluxes cause thearmature, and consequently its shaft, to sing or vibrate t0 the extentof its play. However, since the magnetic pin 14: is kept in a magnetizedcondition under the influence of the horse-shoe magnet 54, there will bea tendency to hold the steel pin 4-8, and consequently the shaft and itsarmature, against this tendency to sing. This is the magnetic cushionwhich has hereinbefore been referred to, and it is clear that the effectof this influence can readily be adjusted, by the arrangement proposed,to meet the requirements.

Secured upon the cradle member 17, under the disk 51, is the auxiliarycross piece In plan, this cross piece is Ushaped and the rearwardlyextending arms thereof are provided with a longitudinal slot 56 throughwhich screws 57 threading into the cradle part, may pass. Thisarrangement provides for moving the cross piece 55 forwardly andrearwardly as desired. To the face of this cross piece the damping orbrake magnets 58, 58 are secured by means of screws 59, 59 passingthrough the retaining plate 60 and threading into the cross piece, asclearly shown in the drawings. These brake magnets are each more or lessC-shaped so as to embrace the disk, the latter operating in the gaps 61,61, as is well known in the art; These brake magnets may be moved towardor away from the periphery of the disk to secure the proper calibration.Near its upper end the armature shaft 16 is provided with a worm 62which meshes withthe worm wheel 3 mounted upon a shaft 64 j ournaled ina suppoiting bracket (35, which, in turn is secured bymcans of thescrews (36, 66 to the underside of the cross-piece 23. The shaft (34carries an arm 65 which is adapted to engage-an arm (57 on the mainshaft (38 of an integrating mechanism carried on and between the plates(59 and 70, which in turn are supported upon the posts 71, 71 extendingfrom lugs 72, 72 on. the cradle. Screws 73, 73 hold the integratingmechanism in place, the arrangement being such that the shaft 68 is then inalinement with the shaft 64, as illustrated in Fig. The

integrating mechanism is provided with a face 74 through which thevarious shafts 7 5, 75 in metric relation, extend, these shafts eachhaving a. pointer 76. which cooperates with the dials painted or printedon the face. In order. that these dials may be exposed to View, thecovering of the casing has an opening 77 in back of which a glass 78 isset in some suitaiblemanner, this opening being preferably of suflicientsize to disclose other parts of the device so that their operation maybe observed.

From the'foregoing it will be seen that all the operating parts areinclosed and well protected. The outside of the casing carriesnothingmore than the lugs 79, 79 for hanging the meter in a convenient placeand a massive insulating block 80 disposed upon the top of the part 7and held in place in the manner best illustrated in Fig. 2. Meters ofthis kind are usually provided with four terminals, two for the shuntcircuit and two for the series circuit, and these I have shown in theway of four similar comparatively heavy rods 81, 81. The insulatingblock 80 is provided with four vertical bores, near the rear facethereof, which are screw threaded to receive the rods 81, 81, which arecorrespondingly threaded upon the outside. The bores are of thatparticular diameter only part way from the bottom of the block, and therods 81 extending considerably below the block and through registeringopenings in the casing part 7 into the casing. Thumb nuts 82, 82 arescrewed upon the rods 81, 81, and with proper insulating washers 83, 83and an insulating strip 84 intervening, serve to firmly clamp the blockupon the casing, the latter being, by these means, thoroughly insulatedfrom each of the rods. In forward alinement with each of the bores inthe block is a pocket 85 in which the heads of screws 86, 80, passingthrough the resulting wall in the block and into the respective rod 81,are deeply disposed. These screws pass into a longitudinal bore 87 inthe rod 81 to clamp in place the proper external circuit wire enteringby way of the part 87 of the bore. The pockets 85 are all covered overby. a metallic plate 88"which is secured in place by means of the thumbscrew 89 threaded upon a stud 90 set in the block 80 in some suitablemanner, this thumb screw being sealed by the wire and seal 91 in thesame manner as has been described relative to the sealing of the coverpart of the tween the terminals a and d, each of these conductorspassinginto the bore 95 in the lower end of the rod 81 and being held inplace by the set screw 96. The terminal a is connected to one side ofthe line and the terminal d is connected to the severed end in that sideof the line. Either the terminal 6 or the terminal 0, since they arebridged by the conductor 98, is connected to the other side of the line,thus putting the current coils in series and the pressure coils inshunt.

It will be seen that the semi-octagonal form of the cradle is veryeffective in distributing the parts so that easy access may be had toany one of them. The entire cradle can be removed from the casing by themere removal of the screws 18 and 19, and with it the coils, armature,magnets, and integrating mechanism. The skeleton formv of the cradleprovides access from the rear after the cradle has been removed from thecasing, and in general it may be said that the skeleton form of thecradle is effective in affording access to any part whatever after beingremoved from the casing.

The insulating block which has been described effectively protects eachof the terminals against crosses, short-circuits, and injurioustampering, and the terminals leave the interior of the casing in amanner so that dust and moisture may not find their way into theinterior.

I claim as new and desire to secure by Letters Patent:

1. In an induction watt meter, an armature, a bearing, a shaft for saidarmature positively resting upon said bearing, and a magneticallyexcited bearing engaging the upper end of said shaft wherein the shaftis held against lateral movement due to the magnetic influence of saidexcited bearing and against movement longitudinally of its axis due toits mechanical engagement with said excited bearing.

2. In an induction watt meter, an armature, a shaft for said armature, ajewel hearing for the lower end of said shaft, which bearing said shaftmechanically engages at all times, a bearing for the upper end of saidshaft, said bearing mechanically holding said shaft against axial play,and magn-ctic means associated with the upper bearing, the magneticinfluence of said magnetic member serving to hold said shaft againstlateral movement in said upper bearing.

3. In an induction watt-meter, an armature, a lower bearing, a shaft forsaid armature positively resting upon said lower bearing, a tip ofmagnetic material for the upper end of said shaft, a bearing forcooperation with said tip to mechanically hold said shaft against axialplay, and magnetic means associated with said bearing, the magneticinfluence of said magnetic means alone serving to hold said tip againstlateral movement in said upper bearing.

4. In an induction watt-meter, an armature, a bearing, a shaft for saidarmature positively resting upon said bearing, a bearing of magneticmaterial for said armature,

said bearing mechanically holding said armature against axial play, anda magnet for exciting said last-named bearing, lateral displacement ofthe armature being prevented by the magnetic influence of said excitedbearing.

5. In an induction watt-meter, an armature, a lower bearing, a shaft forsaid armature positively resting upon said lower bearing, a bearingofmagnetic material for the upper end of said shaft engaging said shaftand mechanically holding the same against axial play, and a magnetadjustably disposed relatively to said bearing for magnetically excitingthe same, lateral displacement of the armature being prevented by themagnetic influence of said excited bearing.

6. In combination, a bearing, a rotatable shaft positively resting atits lower end on said bearing, a magnetically excited bearing for itsupper end, mechanically holding it against axial play, the magneticinfluence of said excited bearing being such as to prevent lateralmovement of said shaft, a disk armature on said shaft, and fieldwindings in inductive relation to said disk.

7 In an induction wattmeter, a supporting member, a bearing in saidsupporting member, a sleeve mounted in said supporting member inalinement with said bearing, a

second bearing member of magnetic material adjustably disposed in saidsleeve, and a magnet adjustably supported upon said supporting memberand having one of its poles .carried upon the oblique walls, and anarmature carried by said cradle in proper association with saidwindings.

9. In an induction watt-meter, a supporting cradle removable from thecasing as a unit, said cradle being of semi-octagonal form and opentoward the front, windings carried upon the oblique walls, cross piecesat the top and bottom of said cradle, and an armature journaled betweensaid cross pieces.

10. In an induction wattmeter, a casing, a cradle removable from saidcasing as a unit, said cradle being semi-octagonal in form and having anupper and a lower cross piece, a jewel bearing in the lower cross piece,a magnetic bearing in the upper cross piece, an armature shaft journaledbetween said bearings, an armature carried by said shaft, and coilscarried by said cradle in association with said armature.

11. In an induction wattmeter, in combination, a casing, a cradleremovable from said casing as a unit, said 0 adle being semioctagonal inform and presenting its open side forwardly, cores secured to the insidefaces of the oblique walls of said cradle, coils mounted on said cores,a disk armature operating between the pole ends of said cores, a shaftfor said armature, bearings for said shaft, and cross pieces on saidcradle in which said bearings are mounted.

12. In an induction wattmeter, a casing, a cradle comprising a back walland side walls mounted in said casing open toward the front, a crosspiece extending across the front of the side walls of said cradle, saidcross piece being adjustable forwardly and rearwardly, an armature diskmounted in said cradle, and a C-shaped damping magnet embracing saidarmature disk and carried by said adjustable cross piece.

In witness whereof, I hereunto subscribe my name this 23rd day ofAugust, A. D.

GUSTAVE A. SCHEEFFER. lVitnesses:

WILLIAM W. HAMMOND, JOHN E. Soorr.

